What this code means
U0146 may indicate that the PCM is not receiving expected communication from the CAN gateway, or that the gateway information may be abnormal.
What the vehicle may do
- The vehicle may show network-related warning lights.
- Some systems may not communicate normally.
- The condition may appear mainly as a stored communication code.
Possible fault areas
- Possible CAN gateway startup issue.
- Possible CAN gateway power or ground concern.
- Possible CAN communication path concern between the CAN gateway and the PCM.
Diagnostic path
Opening context
On this 2020 through 2025 Honda CR-V Hybrid, U0146 is a network communication code in the PGM-FI system. In plain terms, the PCM may not be getting the expected communication from the CAN gateway, or the message coming from that gateway may be abnormal. The vehicle may show network-related warning lights, some systems may not communicate normally, or the symptom may only show up as a stored communication code. The broad fault areas here are the CAN gateway starting up correctly, its power and ground supply, and the CAN communication path between the gateway and the PCM.
How the code sets
The logic for U0146 is straightforward: if the PCM cannot receive a signal from the CAN gateway through the PF-CAN N line or the PD-CAN P line, or if the information sent from the CAN gateway stays abnormal for the required cycle, the PCM decides there is a fault and stores the code.
Start of diagnosis
Start with the basic system checks and keep the diagnosis structured. Before going deeper into the network side, check the CAN gateway power and ground circuit first. That matters because this code may be stored if the CAN gateway does not start normally, and it may also be stored when the gateway has a power or ground circuit failure.
Network diagnostic direction
Once the CAN gateway power and ground check is handled, the diagnostic path moves into the F-CAN lost-communication direction for the CAN bus connection to the CAN gateway. The detailed branch testing for that path is not available here, so do not guess at pin checks or replacement calls. Pause, recheck the earlier diagnostic path, and continue only with the proper network test information in front of you.
Code confirmation
For confirmation, turn the vehicle to ON mode and wait 6 seconds. Keep this separate from the actual circuit testing: this is the monitor confirmation step, not proof by itself that a specific part has failed.
Closing takeaway
The key on U0146 is not to jump straight to a module call. Make sure the CAN gateway can power up correctly, confirm its ground path, then follow the lost-communication path for the gateway network. Verify the repair and confirm the code stays gone. For more diagnostic training, visit stepdiagnostics.com.
Final check
U0146 is best approached as a gateway power, ground, and network communication diagnosis before considering any module-level conclusion.
For more guided automotive diagnostics, visit STEP Diagnostics.
